氢化物原子荧光光谱法直接测定尿中微量铅

目的：建立快速测定尿中微量铅的氢化物发生原子荧光光谱法。方法：微量尿样经酸稀释后，直接与硼氢化钾反应产生铅的氢化物，用AFS-920双道原子荧光光度计进行测定。结果：在本法条件下绘制标准曲线在0．0～10．0μg／L浓度范围内线性关系良好，相对标准偏差（RSD）为1．36％，检出限0．02μg／L，加标回收率为92．4％～104．3％。结论：直接酸稀释原子荧光测定尿铅是一种准确、快速、简便的方法，适用于广泛推广。     

气相色谱法测定水、土壤中六甲基磷酰三胺

目的：初步建立气相色谱法测定水、土壤中六甲基磷酰三胺（HMPA）的方法。方法：在碱性条件下，样品经氯仿萃取，毛细管气相色谱一氮磷检测器（NPD）测定，以保留时间定性，峰面积（或峰高）外标法定量。结果：在最佳分析条件下，样品中HMPA在1～2000μg／L范围有良好线性关系（r〉0．99），方法检出限为1ng，回收率为86％～101％，精密度为6％（0．05μg／ml），4．6％（1．0μg／ml）。结论：本法测定水、土壤中HMPA简便、快速、灵敏、准确。     

塞曼石墨炉原子吸收光谱法直接测定职业接触者血液中铝

目的：建立石墨炉原子吸收光谱法直接进样测定职业铝接触者血液中铝的方法。方法：以Triton X-100为血液基体稀释剂，K2Cr2O7为基体改进剂，通过准确选择干燥、灰化及原子化条件，直接进样测定。结果：血铝浓度为0～120μg／L时，方法的线性关系良好，相关系数r=0．9993。检出限为0．95μg／L，加标回收率为93.0％～103.2％，相对标准偏差（RSD）为3．5％。7．1％。结论：方法简便，灵敏度高，精密度好，结果准确，适用于测定职业接触者血液中铝。     

氢化物发生-原子荧光光谱法同时测定保健食品中砷和锑

目的：研究了氢化物-原子荧光光谱法测定保健食品中砷和锑的适宜条件，研究了酸介质和还原剂的用量对测定砷和锑的影响，选择了仪器的最佳工作条件及氢化物发生条件，探讨了生成氢化物元素及常见元素对测定的干扰情况。方法：采用氢化物-原子荧光光谱法进行测定。结果：在测定条件下，砷的线性范围为0～80μg／L，r=0．9998，检出限为0．6μg／L，回收率在96．9％～110．7％之间，精密度（RSD）为9．3％；锑的线性范围为0～80μg／L，r=0．9999，检出限为0．27μg／L，回收率在89．2％～110．6％之间，精密度（RSD）为2．69％。用该法测定了标准物质茶叶中砷和锑的含量以进行比较，结果与推荐值相吻合。结论：方法快速、准确，应用于保健食品中砷和锑的检测，获得较满意结果。     

微波消解原子荧光光谱法同时测定罐头食品中硒和锡的研究

目的：建立微波消解原子荧光光谱法同时测定食品中硒和锡的方法。方法：对微波消解原子荧光光谱法同时测定硒和锡的各参数条件进行研究。结果：在最佳测试条件下，硒方法检出限为0．3μg／L，测定相对标准偏差为1．0％～2．0％，样品加标回收率为96．8％～98．6％。锡方法检出限为0．3μg／L，测定相对标准偏差为2．7％～3．4％，样品回收率为92．7％～96．2％。结论：本法具有快速、准确、灵敏度高、精密度好等优点，用于罐头食品中硒和锡的测定，结果满意。     

微波消解-原子吸收分光光度法测定茶叶中的微量元素

目的：建立微波消解-原子吸收分光光度法测定茶叶中4种微量元素的分析方法。方法：样品经微波消解，用原子吸收分光光度法测量微量元素。结果：方法检出限分别为Cu：0．022μg／ml、Fe：0．15μg／ml、Mn：0．021μg／ml、Zn：0．060μg/ml；线性范围分别为Cu：0．2—3．0μg／ml、Fe：0．3—5．0μg／ml、Mn：0．2—4．0μg／ml、Zn：0．1～0．6μg／ml，相关系数r≥0．999；相对标准偏差（RSD）分别为Cu：2．18％、Fe：8．02％、Mn：3．12％、Zn：7．15％；回收率分别为Cu：99．4％-102．8％、Fe：94．7％～104．7％、Mn：98．9％～101．1％、Zn：87．5％-108．1％。结论：该法消解效果理想，检出限低，线性范围较宽，精密度好，准确度较高。     

安替比林与亚硝酸根相互作用分光光度法测定亚硝酸根

目的：测定肉与肉制品中微量亚硝酸根含量。方法：在硫酸介质中，安替比林与亚硝酸根相互作用，生成亚硝基安替比林，该溶液最大吸收波长为345nm。据此建立测定亚硝酸根的方法。结果：线性范围为0～3μg／ml，检出限为0．08μg／ml。对浓度水平为1．0μg／ml亚硝酸根的10次平行测定的RSD为2．3％。结论：方法应用于肉与肉制品中微量亚硝酸根含量测定，结果满意。     

高效液相色谱法测定保健食品中大豆异黄酮

目的：建立测定保健食品中大豆异黄酮含量的高效液相色谱法。方法：通过对流动相的优选，以甲醇：水=3：2为流动相，使染料木素、大豆苷元、大豆甙、染料木甙4种大豆异黄酮主要成分达到较好的分离效果，可分别测定4种成分含量及以此4种成分为主要成分的保健食品中大豆异黄酮含量。结果：方法的最低检出浓度分别为大豆甙1．9μg／ml、染料木甙1．2μg／ml、大豆苷元1．0μg／ml、染料木素0．8μg／ml；标准曲线线性范围分别为1．9—100μg／ml、1．2—100μg／ml、1．0—170μg／ml、0．8～140μg／ml；方法平均回收率分别为99．1％、98．5％、97．5％、98．8％；相对标准偏差均（10％。结论：建立的方法可准确、快速的测定大豆异黄酮的含量。     

同位素内标稀释高效液相色谱-质谱法测定鱼体中的孔雀石绿及其代谢物

目的：以同位素内标稀释建立了测定鱼体中孔雀石绿及其代谢物的高效液相色谱-串联质谱法。方法：试样中加入氘代同位素内标，用柠檬酸缓冲液／乙腈提取，液液分配后SCX净化，MRM定量。结果：方法的线性范围为0.5～10μg／L，线性系数为0．9992，检出限为0．1／μg／kg。在1．0、1．5、2．0μ/kg3个浓度水平加标回收率为94％～104％,rsd为4．7％～5．9％。结论：该方法灵敏度高，准确度、精密度好，满足了样品测定的定性、定量要求。     

高效液相色谱法测定空气中苯胺和N-甲基苯胺的研究

目的建立高效液相色谱法同时测定空气中苯胺、N-甲基苯胺的检测方法。方法应用高效液相色谱，C18通用色谱柱，以甲醇为流动相，流速0．7ml／min，紫外检测器在240nm波长下测定吸收值。，结果苯胺线性范围0．00～1000μg／ml，回归方程：Y=0．000936x＋0．6769，相关系数r=0．9999，最低检出浓度1．0μg／ml，空气中最低检出浓度0．22μg／m^3，在250、25、2．5μg/ml浓度下测得平均回收率分别为：99．2％、100．5％、104．4％，相对标准偏差RSD分别为0．23％、0．42％、3．25％；N-甲基苯胺线性范围0．00～1000μg／ml，回归方程：Y=0．00124x＋0．02，相关系数r=0．9999，最低检出浓度0．4μg／ml，空气中最低检出浓度0．09μg／m^3，在250、25、2．5μg／ml浓度下测得平均回收率分别为：99．7％、101．6％、102．0％，相对标准偏差RSD分别为0．27％、0．23％、3．65％。结论分析时间短，相关性好，精密度高，准确度好。特异性强，该法线性范围宽。     

Calcium intake in the elderly: validation of a dietary questionnaire

Epidemiological studies of calcium and osteoporosis have been hampered by the lack of a suitable tool for assessing calcium intake. This report describes a new frequency and amount questionnaire for measuring present and past calcium intake in the elderly. The validity of the questionnaire was tested against two commonly used standards of dietary assessment, five-day duplicate diets and seven-day weighed dietary inventories. The resulting correlation coefficients were, respectively, r = 0.76 and r = 0.69, while that for repeatability was r = 0.84. Furthermore, the questionnaire categorized subjects into thirds of the distribution of intake with almost no gross misclassification. It is suggested that the present findings may be extended to the majority of normal, healthy elderly subjects, implying wide application for the questionnaire in the assessment of calcium intake in the elderly.     

Self-reported health problems among Swedish miners one year after unemployment

Unemployment is considered to be a public health concern sincedeterioration in the health of the unemployed is often anticipated.However, for some groups, such as miners, unemployment mightimprove health due to a cessation of potentially harmful occupationalexposures. This study evaluates the health of 79 miners in oneSwedish iron-ore mine, and 226 age-matched controls from thegeneral population, during one year after the closure of themine. The participants received a questionnaire regarding medicalhistory and subjective symptoms at the beginning of the studyperiod, and after one year. Statistically significant negativeeffects on self-reported health attributable to unemploymentwere not found, although neuropsychiatric symptoms were morecommon among the unemployed miners. The miners reported a statisticallysignificant improvement in grip force (p=0.031). They had asignificantly higher prevalence of symptoms associated withmining related exposures when compared with the population controls;pain in the upper extremities [relative risk (RR)=2.27, 95%confidence interval (Cl)=1.44–3.59), back pain (RR=1.84;Cl=1.237–2.75), vasospastic disease of the fingers (RR=2.05;Cl=1.18–3.57) and obstructive respiratory symptoms (attacksof dyspnea and wheezing: RR=3.67; Cl=1.167–11.6).     

Excès de cas humains et animaux de tularémie en France au cours de l’hiver 2007–2008 : émergence ou phénomène isolé ?

Context

Tularemia is a zoonosis affecting humans and hares in France. We describe the results of surveillance in both species, in 2007 and 2008.

Methods

Human tularemia cases are mandatorily notifiable in France since 2003. In hares, surveillance relies on volunteer hunter associations in all districts of the country. Data from mandatory reports and volunteer surveillance in 2007/2008 were analyzed and compared with previous results.

Results

In 2007/2008, 144 cases were reported in humans and 117 cases in hares. This was a 100% increase compared to previous years. Human cases differed from those of previous years only by the frequency of contact with breeding animals. Human cases without any documented risk exposure were also more frequent.

Conclusion

An increase of tularemia cases occurred in 2007/2008 in both species. Complementary studies are needed to identify the species reservoir in France to understand the causes of this peak of cases.     

Occupational health hazards in mining: an overview

This review article outlines the physical, chemical, biological, ergonomic and psychosocial occupational health hazards of mining and associated metallurgical processes. Mining remains an important industrial sector in many parts of the world and although substantial progress has been made in the control of occupational health hazards, there remains room for further risk reduction. This applies particularly to traumatic injury hazards, ergonomic hazards and noise. Vigilance is also required to ensure exposures to coal dust and crystalline silica remain effectively controlled.     

Manufacture and use of nanomaterials: current status in the UK and global trends

This paper provides an overview of the production and use of nanomaterials (NMs), particularly in the UK. Currently, relatively few companies in the UK are identifiable as NM manufacturers, the main emphasis being the bulk markets in metals and metal oxides, and some niche markets such as carbon nanotubes and quantum dots. NM manufacturing in the UK does not reflect the global emphasis on fullerenes, nanotubes and fibres. Some assumptions have been made about the types of NM that are likely to be imported into the UK, which currently include fullerenes, modified fullerenes and other carbon-based NMs including nanotubes. Many university departments, spin-offs and private companies have developed processes for the manufacture of NMs but may only be producing small quantities for research and development (R&D) purposes. However, some have the potential to scale up to produce large quantities. The nanotechnology industry in the UK has strong R&D backup from universities and related institutions. This review has covered R&D trends at such institutions, and appropriate information has been added to a searchable database. While several companies are including NMs in their products, only a few (e.g. manufacturers of paints, coatings, cosmetics, catalysts, polymer composites) are using nanoparticles (NPs) in any significant quantities. However, this situation is likely to change rapidly. There is a need to collect more information about exposure to NPs in both manufacturing and user scenarios. As the market grows, and as manufacturers switch from the micro- to the nanoscale, the potential for exposure will increase. More research is required to quantify any risks to workers and consumers.     

深圳公立医院管理体制改革制度设计

深圳公立医院管理体制改革实行政事分开、管办分开,在理事会架构下按法定机构模式组建市医管中心,落实公立医院运营管理自主权.作者从当前公立医院管理体制的弊端入手,介绍了深圳市进行公立医院管理体制改革的基本思路及改革方案设计的主要举措,深入剖析了的改革方案的特点,并对改革效果进行了预测.     

Effects of nitrogen dioxide on red blood cells of rats: Changes in components of red cell membranes during in vivo exposure to NO2

Red cell membranes, prepared from red blood cells of rats exposed to 4, 10, or 20 ppm nitrogen dioxide (NO₂) for 1 to 10 days, were examined for evidence of changes in membrane components. Appreciable changes were not found in contents of phospholipid and cholesterol during exposure to 10 ppm NO₂. By contrast, protein content altered with the time of exposure. Moreover, changes in protein composition were observed by employing sodium dodecyl sulfate — polyacrylamide gel electrophoresis. Twenty-four-hour exposure to NO₂ at the concentration above 10 ppm resulted in a marked increase in the percentage of lysophosphatidylethanolamine (LysoPE) to the total phospholipids. The prolonged exposure to 10 ppm NO₂ gave rise to a further increase in LysoPE, whereas the percentage of phosphatidylethanolamine (PE) showed a gradual decrease. A 1-day exposure to 4.0 ppm NO₂ also caused an increase in sialic acid content and decreases in those of PE and hexose. In addition to contents of these components the percentage of LysoPE increased 5 days after exposure and the elevated values were maintained up to the end of exposure period. These results demonstrate that red blood cells in circulation exhibit different membrane properties in terms of lipid and carbohydrate composition during 10 days of exposure to 4.0 ppm NO₂.     

Investigating clusters in the workplace and beyond

Clusters of disease are common and occur in the workplace and in the general community. They often arouse considerable concern among the population. Investigations have sometimes lead to exciting new knowledge, but in general the investigation of clusters is difficult and often unrewarding, especially for community clusters. In the workplace, investigations are more likely to find associations and even new causes, but still many clusters remain enigmatic. Despite this, there are many reasons for investigating clusters, including allaying community concern and identifying uncontrolled exposures. A structure for investigating clusters in the workplace is suggested.